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Divers Caught Cutting Internet Backbone Cable

Egyptian saboteurs damage cable, affect service across northern Africa and Asia

1 min read
Divers Caught Cutting Internet Backbone Cable

What’s the least sophisticated, but probably the most foolproof, way to cut off a country’s Internet traffic? Literally cutting it by severing undersea Internet cables. That’s what the Egyptian navy caught three scuba divers doing in the waters 750 meters off the port city of Alexandria on Wednesday. The cable they were going after was the 18 000-kilometer-long South East Asia–Middle East–Western Europe 4 (SEA-ME-WE 4) line, the Internet backbone that carries data between Europe, Africa, the Indian subcontinent, and Malaysia and Singapore in southeast Asia.

Internet service in Egypt had already been off since 22 March, supposedly because a passing ship damaged a separate cable. The trio, who approached “hacking” from a different angle than usual, took to the water a day before repairs to the other cable were expected to be completed and service restored.

The effects of the ship taking out that cable were experienced as far away as Pakistan and India, Jim Cowie, chief technology officer at Renesys, a network security firm, told the Associated Press. Cowie noted that a severed cable can force wide scale data rerouting, with some of the packets traveling the long way around the world.

Ship anchors and propellers have been blamed for serious cable breakages in the Mediterranean that affected northern Africa. Perhaps this incident will cause investigators to cast a more jaundiced eye in future cases.

Illustration: TeleGeography

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Metamaterials Could Solve One of 6G’s Big Problems

There’s plenty of bandwidth available if we use reconfigurable intelligent surfaces

12 min read
An illustration depicting cellphone users at street level in a city, with wireless signals reaching them via reflecting surfaces.

Ground level in a typical urban canyon, shielded by tall buildings, will be inaccessible to some 6G frequencies. Deft placement of reconfigurable intelligent surfaces [yellow] will enable the signals to pervade these areas.

Chris Philpot

For all the tumultuous revolution in wireless technology over the past several decades, there have been a couple of constants. One is the overcrowding of radio bands, and the other is the move to escape that congestion by exploiting higher and higher frequencies. And today, as engineers roll out 5G and plan for 6G wireless, they find themselves at a crossroads: After years of designing superefficient transmitters and receivers, and of compensating for the signal losses at the end points of a radio channel, they’re beginning to realize that they are approaching the practical limits of transmitter and receiver efficiency. From now on, to get high performance as we go to higher frequencies, we will need to engineer the wireless channel itself. But how can we possibly engineer and control a wireless environment, which is determined by a host of factors, many of them random and therefore unpredictable?

Perhaps the most promising solution, right now, is to use reconfigurable intelligent surfaces. These are planar structures typically ranging in size from about 100 square centimeters to about 5 square meters or more, depending on the frequency and other factors. These surfaces use advanced substances called metamaterials to reflect and refract electromagnetic waves. Thin two-dimensional metamaterials, known as metasurfaces, can be designed to sense the local electromagnetic environment and tune the wave’s key properties, such as its amplitude, phase, and polarization, as the wave is reflected or refracted by the surface. So as the waves fall on such a surface, it can alter the incident waves’ direction so as to strengthen the channel. In fact, these metasurfaces can be programmed to make these changes dynamically, reconfiguring the signal in real time in response to changes in the wireless channel. Think of reconfigurable intelligent surfaces as the next evolution of the repeater concept.

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